Eaton / Cutler-Hammer LA3400 Molded Case Circuit Breaker

Yes. When Eaton acquired the Westinghouse distribution equipment division, they retained the same physical L-frame dimensions and catalog numbers. A Cutler-Hammer or Eaton LA3400 will seamlessly replace an original Westinghouse unit.

The LA3400 can be upgraded to an Eaton Series C LD3400. The LD3400 serves as a direct cross-reference and fits into the same Pow-R-Line 4 panelboards and motor control centers without physical modifications.

This L-frame breaker is specifically designed for bolt-on installation in classic Eaton and Westinghouse panelboards, commercial switchboards, and motor control centers.

Yes. While the standard lugs support a single large conductor up to 600 kcmil, they can also accommodate dual parallel runs ranging from 3/0 AWG to 250 kcmil for both aluminum and copper wire.

This breaker utilizes a thermal-magnetic trip unit with a fixed thermal element for long-time overload protection and an adjustable magnetic element. This allows electricians to dial in instantaneous trip settings to coordinate with downstream devices and specific motor loads.

Yes. The standard terminal lugs on this breaker are rated for use with both aluminum (Al) and copper (Cu) conductors. Always apply the appropriate oxide inhibitor when landing aluminum wire to prevent corrosion and overheating.

Ensure the main power is completely de-energized and locked out. Because this is a 400-amp frame, always verify that the busway or panelboard interior has not suffered heat damage or pitting from the outgoing obsolete breaker before installing the replacement.

It offers a 30 kA interrupting rating at 480V AC, which is suitable for many standard commercial applications. If your facility fault current study dictates a higher rating, you will need to source the high-interrupting HLA3400 or upgrade to a modern HLD3400 Series C breaker.